Recovery of the unsaponifiable fractions of fatty materials



solvent.

Patented May 16, 1950 UNITED STATES PATENT OFFICE RECOVERY OF THE UNSAPONIFIABLE FRACTIONS F FATTY MATERIALS Loran 0-. Bnxton, Maplewood, N. J., assignor to Nopco Chemical Company, Harrison, N. J., a corporationoi New. Jersey 'No Drawing. Application March 1946, y Serial'No. 654,791

19 Claims.

The present invention relates to. the purification and concentration or recovery of the unsaponifiablefraction of an. oil. or fatand more particularly to a process for producing a fatsoluble vitaminconcentrate from an oleaginous material containingvitamins, as, for example, fish livera-nd other vitamin-containing oils of marine or vegetable origin.

In PatentN'o.v 2,318,749, there is. disclosed a. processpfor'producing atatssoluble vitamin content, addinga-hydrocarbon or halogenated hydrocarbon solvent to the soap, and heating the solvent and soap to a temperature T of about 60 orft0 The soapssolvent mass is then cooled to iroom 'temperature'and' a quantity of water added to: facilitate the separation of the soap from thesol-vent. Thereafter, the soap layer is separated from the solvent layer and extracted "with successive heating and cooling to room temperature withssuccessive quantities. of additional Although the aforementioned process is: successful; in producing vitamin concentrates in:a; relatively "high yield-,1 large amounts of solvent, are necessarily used, as it was thought preferable to actually dissolve: thesoap in the solvent upon heating, and the time involved for-theprocrelatively long. For example, the cooling otthe mass to room temperature prior to the addition of the-water to effect; separation takes :pIace over several hours, andthe clean separation orthe soap irom the solvent after the addition of thewater generally' consumes an additional severalhours time. Further, the relatively slow cooling and necessaryagitation cause reresultant vitamin concentrate, when produced, has a relatively: low: potency when tested by the bio-assay method. In U. S. Patent'No. 2,318,748,

a somewhat similar process/to that: outlined has "been disclosed, except that the sapon-i-fication takes place in the-presence oi a-suitable solvent. ln'accor'dance with. the U. S. Patent application Ser. No. 486,2145. now abandoned, it was discovered thatthc'soap couldbe separated from the solvent at elevated temperatures, as, for example, from 40 to 8fi Caandipreferably between 66am 70"C., provided, answers-pointed out, that the. total water content. of the saponifledmass 'Was kept within a critical range of between 23 and It has now been discovered, however, that in actual plant practice, the critical range varies substantially with the type of. oil being treated. In other words, long chain acidspresent in an oil tend to make the character of the produced soap harder, while unsaturated groupings tend to make the produced soap softer. Even though a hard soap is produced, however, from a given oil, this type of soap also tends to; occlude more of the unsaponifiable material, and it is therefore necessary to add water in order to change the character oi the. soap so that the same will have a looser structure. In the. case of softer soaps, water must also be added to decrease solubility. However, if too much water is added to a soap, the soaptends tov have. an increased. affinity for the unsaponifiable material, even though the structure of the soap may be more desirable for extractionand, therefore, it may be stated that the less water that. can, be used, with any particular type of oil, the less solvent will be. necessary for an efiicient extraction.

Further, the higher the water content, the greater the tendency'for the soap to emulsify in the solvent upon stirring, so as to. render separation at the elevated temperatures involved in accordance with the present invention difficult. It is for this reason that in any event in practicing the present process, agitation and stirring of the soap mass and extracting solvent bekept at a minimum consistent with efficient extraction.

In general, it has been new discovered, that when proceeding with the hot extraction of, .the saponified oils with a suitable solvent, the total moisture contentv of the soap can be varied from 12 to 35% and, in some instances, as, high as 5.0%. However, the best manner of determining the quantityof water to be added. is that such quantity of moisture be present in the soap so that the soap will be-slightly soluble at temperatures just below the boiling point of the solvent.-. used. For ethylene dichloride, the preferred solvent, thistem-perature is between 40 and 70 C. and preferably between and. C. In otherwords, it has been discovered that if from .to. 5% oi the soap, and preferably somewhat less than. 1%, is soluble in' the solvent, as, for example, ethylene dichloride, the character of the soap is-such that a minimum amount of solvent can be used'tor the extraction of unsaponifiable matter and that further, if the moisture contentof, the, soapis within this range, the separation of thesoap 3 layer from the solvent is substantially instantaneous so that the process of extraction can be carried out in a minimum of time with a relatively small amount of solvent. As a result, not only are the yields of vitamin in the concentrates obtained in accordance with the present process somewhat greater in plant practice than those produced when proceeding in accordance with the aforementioned prior patents, but the concentrate produced exhibits a general increase in actual potency as determined by bio-assay tests. Further, because of the ease of separation and extraction at these relatively high temperatures, the concentrates produced have been eXposed to contact with alkali, i. e. soaps for the shortest possible period of time so that peroxide formation with consequent oxidation losses are maintained at a minimum, 1. e. the vitamin concentrates as produced in accordance with the present process are in general more stable. An object of the present invention is to provide an improved process for the recovery of unsaponifiable fractions of naturally occurring Ifatty material.

A second object of the present invention is to provide an improved process for the recovery or production of unsaponifiable fractions or concentrates of various oleaginous materials by saponification followed by subsequent separation and extraction of the soaps formed.

A third object of the present invention is to *provide an improved process for the production of vitamin concentrates by the saponification of various types of vitamin-containing oleaginous material followed by subsequent separation and extraction of the soaps formed.

'A fourth object of the present invention is to provide a process for the separation of saponified matter from unsaponifiable material in various fatty materials, this separation and also subsequent extraction being effected in the shortest possible time and with a minimum of solvent.

A fifth object of the present invention is to provide a process for the separation of saponified material from unsaponifiable material present in vitamin-containing oils, said separation and ex-- traction of the material being effected in the shortest possible time and with a minimum of solvent.

A sixth object of the present invention is to provide a process for the preparation of vitamin concentrates from fish liver oils and the like in a minimum amount of time and with the use of a cholesterol, stigmasterol, phytosterol, lanosterol,

agnosterol and other sterols as free alcohols or esters, high alcohols, q'uinols, quinones, squalene and the like.

An eighth object of the invention is to provide a simple, economical and efiicient process for the separation of substantially all of the unsaponifiable matter from the saponifiable substances in a wide variety of fatty materials; the process being operative regardless of the proportions of saponifiable to unsaponifiable matter in the fatty material.

Other objects and advantages of the present invention will become apparent from the present "specification and claims.

In carrying out the process of the invention, any suitable saponifiable oil or fat from which the recovery of the unsaponifiable fraction is desired, may be used in efiectuating the purposes of the invention. The unsaponifiable fraction of various animal, vegetable and'marine oils and fats contains valuable byproducts when separated from their fatty vehicle. Many oils contain sterols and more particularly the fat-soluble vitamins A, D and'E and provitamin A. While the present invention may be applied to various oils, it has particular value in the production of the fat-soluble vitamin concentrates which are derived from fish liver oils and certain animal and vegetable oils; the vitamin A and/or D containing oils include, among others, the oils produced from various fish and their livers, such as cod, sardine, halibut, tuna, shark, dogfish, ling cod, pollack, sword, pilchard, whale, and other fish. Provitamin A may be concentrated according to the invention from various vegetable oils, such as palm. oil and carrot oil, and vitamin E may be recovered from wheat germ, rice bran and like oils.

The unsaponifiable fractions of various oils and fats including lard, tallow, porpoise, whale, seal, corn, soybean, pine, cottonseed, linseed, oat, millet seed, rice bran, rye, wheat, rape seed, mustard seed, sesame, sunflower seed, perilla, tall oil, teaseed, acorn, cashew nut, cofiee bean, hazel nut, horse chestnut, kapok, pecan, walnut, apricot kernel, tomato seed and pumpkin seed oils and the like are valuable products in and of themselves and may be recovered in accordance with the process of the invention. In general, the unsaponifiable matter in these oils contains sterols, higher alcohols and related substances. The sterols usually occur as either free alcohols or esters; such esters are hydrolyzed to free alcohols during the saponification reaction. To mention only a few specific examples, cholesterol is found in lard, tallow, whale and porpoise oils and in wool grease. In addition, wool grease contains isocholesterol which is a mixture of lenosterol and agnosterol. Stigmasterol and other sterols, as well as quinols and quinones, are present in soybean, cottonseed and corn oils. Phytosterol occurs in the unsaponified material in pine, corn and tall oils. Whale and porpoise oils yield hydrocarbons such as squalene.

In accordance with this invention, the first step comprises the production of a saponified mass containing soaps and unsaponifiable matter by treating a suitable fat or oil with alkali. The resultant saponified mass, either immediately or after certain intermediate manipulations, is extracted with a solvent at high temperature and with the total water content adjusted within the critical range above set forth. The saponification may be effected by various alkalies, such as potassium hydroxide, sodium hydroxide, sodium carbonate, etc., although potassium hydroxide is preferred; may be carried out under various conditions, for instance in solvent solution, with or without the presence of catalysts, etc.; and may be carried out either completely or to any desired degree, for instance, a less than stoichiometrical quantity of alkali may be employed so as to secure selective saponification of only certain components in the oil. Moreover, the high temperature extraction need not be the first extraction, separation or other manipulation carried out upon the saponified mass; for

instance, a saponified mass can be extracted with solvents one or more times in the ordinary way at low temperatures, followed (with adjust- :apoaaao ment ofsthe wateracontent to the critical range if itfzls not..=already within. that range) :by :one or imore solvent z-aextractions .aat high temperature. 'Norsit is essential that: the extractiontbe "carried loutcbymeanssofnsolvents :freshlyadded after the saponification; for instance, .all :or a part of the solventmay-xhave'been: present during the saponiiication. i .In abrief, the salient .ieatures "of this invention consist in first. preparing, "from :an oil aeontaining 1 unsaponifiable matter, a mass which ountains, in "intimate contact-soaps of the saponiflable matter in' theoil, the unsaponifiable matter oilpthe..selected'solvent,1and water, inlsuch iamount' that the soap is. slightly soluble inthe solventaata temperature just below thejb'oiling .pointihereof. The temperature .ofthis mass is ithe'n'zraised, if it is not already raised,rto a temperature between about 40" sand about 80" C. "(preferablybetween about 60 and about-70?C0 rand: the solvent, containing dissolved unsaponifiable matter; is mechanically separated from the mass. The water necessary to render the soap only slightly soluble in thesolvent may be added either with. the alkali or after saponification.

TTIhe extraction. steps according .to this. inventionmay be carried out. by the use. of any suitable hydrocarbon or halogenated hydrocarbon solvent or mixture thereof, it being preferred, however, to .usea halogenated hydrocarbon solvent, and particularly ethylene. dichloride. This solvent, besides eifectively extracting unsaponifiiable matter from .saponified masses, has the "furtheradvantage of .high density, so that it spontaneously settles to. the bottomafter any 1 extractive manipulations and can readily be drawn ofi. However, other-solvents such as trichlorethylene, trichloroethane, heptane, octane, methyl'cyclohexane, :carbon.tetrachloridaand the like :may:-be .use'd. Preferably, .the .amountof solvent used isilimited, inasmuch asathesoap; as

:before'rpointed out,.-is soluble to .a slight extent :therein. The amount .of solvent-usedfor each extraction 1 may varybetween: an. amount equal to= the-weight of the original Oil being. treated, to about six times the quantity of 1011 being :treated. In -general, the amount of solvent used for the. first extraction is .somewhat'tgreatr' than .that used for subsequent extractions. Prefersably, forthegfirstzextraction inaxtypical case,

an amount of solvent about four times the amount of: the oil is used and forsubsequentexx'tractions, this quantity-ofisolventmay:be reduced until it is about equal"tothe-amountof oils-being treated.

LAsrb'ef-ore pointed out, whenscarrying outthe ..process: at the a preferred: range :of' temperatures, thestructure of the soapexhibits arzminimum .aifinity for :theunsaponifiable material and $01- v:vent; and. itwhas been discovered that when pro- ,ceeding in accordance with the presentprocess,

only from. 41=to8 extractions are. necessary to re- ..moveall of the unsaponifiable material from .the soap. Each-of these extractions takes place .inra minimum-of: time, since the: separation of theisoap 'fromthe oil and. solvent issubstantially =instantaneous. Preferably during extraction, agitation islkeptatza minimum.

:Inyproceeding in accordance with the present "process, the saponification may take place in the conventional manner, either with the. addition of a suitable saponification catalyst such .as...an alcohol; or without suchaddition. Heat is-usua'lly generated duringisaponification, or .the mass may be heated to aaslight'extent .so that the final saponification mass is already above roomtemperature. If the temperature vof the :mass is belowthe temperature desiredfor-extraction, it: may then be heated slightly, or preferably, the solvent is added in abut condition. If :an addition. of water is necessary to adjust the water content of the sea-p so that it is only .slightlysoluble insthe. solvent, it is added after the solvent has been mixed with theoil so that emulsification due to prolonged agitation 'may be minimized andpreferably in a heated con- :ditioncso thatat notime is'the mixtureofnsolvent and soap substantially cooled. The-soap isthen separated from the solution of unsaponifiable material? in the solvent-and the soap mass again "treated with an additional quantity, as before set forth, of heated solvent, so that the temperature in all extractions inthe case where ethylene'zdichloride is used is preferably approximately to (3.; although as before stated, the amount of water in the soapisadjustedso that a small quantity as, for example, from-V to- 5%, and-preferably somewhat-less than 1%, of 'the'soap isdissolved in the solvent,'it' is-to be understood that this is' true only of the initial extractiom-and'if the amount of water is thus adjusted, at much lesser quantity is usually dissolved during subsequent extract-ions. 'Violent and prolonged agitation is also avoided during the subsequent extraction. After: the extractions 'havebeen'separated, they may then be combined and the small amount of soap dissolved removed :by cooling the extracts. Inasmuch" as the amount of soap is very small in quantity, the-amount of unsaponifiable material. entrained in the soap upon cooling is also negligible in amount.

".Whenother solvents than ethylene dichloride are used, the temperature may be somewhat higher than that mentioned and general lim- .ited: by theboiling point of the. specific solvent. "In-=..no case,:however, should the temperature used be below about 40 C. as the structure of the soap, as before stated, renders quick separation and extraction difficult.

The presentinvention isillustrated but isnot intended .to be limited by. the following examples in which all. proportions are expressed in terms of weight.

EXAIWPLE I 1005v pounds of Mexican sharp liver oil having .a vitaminA content of 37,500 units of vitamin A per gram were saponified with 362 pounds of concentrated aqueous potassium hydroxide. It isto be noted that the 362 pounds of alkaline solution were equivalent to the desired per- :centage ofsaponification of the saponifiable materiaL which was The saponification was performed while stirring in a kettle and proceeded rapidly. The temperature at the end of about 30 minutes was about 55. The percentage of water in the formed soap was approximately 13.8%. Thereafter, 5200 pounds (500 gallons) of-ethylene dichloride, preheated to a temperature of 65 C., were added over a period of 15 minutes while stirring rapidly. The stirring was then stopped and 25 pounds of water added with a-minimum amount of stirring necessary for thoroughly admixing the water with the soap-and ethylene dichloride. A sharp separation of the ethylene dichloride extract and the'soap stockztook place almost instantaneously .andremoval of, the ethylene dichloride portion wasybegun. .At. the beginning of the removal, it "waspbserved that a somewhat larger amountcof :soapwwas soluble in thesolvent than desired.

extraction.

Thereupon, 25 more pounds of water were added, and the mass was again slightly stirred. The extraction was then finished, and the ethylene dichloride extract removed. The average actual 'temperature of the combined ethylene dichloride and soap mass during this extraction was approximately 60 C. After the first extraction,

:five more extractions were carried out with successive amounts of hot ethylene dichloride.

However, only 3120 pounds (300 gallons) of ethylene dichloride were used for each successive It is to be noted that after the fourth extraction, the extracts were colorless, indicating that most of the unsaponifiable matter had been extracted. After the first extraction, the stirring, as each batch of ethylene dichloride was added, was limited to 1-2 minutes in order to avoid any danger of the soap, which .now contained approximately 16.8% of water,

from emulsifying which would have rendered separation of the soap and ethylene dichloride layers more difficult. With minimum stirring, thestratification of the soap and ethylene dichloride was almost instantaneous, and the removal' of the ethylene dichloride could be effected quickly. The ethylene dichloride extracts were combined and cooled to remove the small amount of soap dissolved. The amount of soap dissolved in the combined extracts was approximately 8 pounds. The ethylene dichloride was then removed by vacuum distillation to produce a vitamin concentrate. The following yields were obtained.

(Ls equal 1,000,000 U. S. P. units of vitamin A) Input'weight oil pounds 1005 Input vitamin A-uns-ap. basis Ls 16,864

Output yield (unsap.) pounds; 90.5

Output yield vitamin A Ls 16,964

Output yield vitamin A per cent" 100.59

EXAMPLE II 1250 pounds of another lot of Mexican shark liver oil having a vitamin A content of 37,700 units of vitamin A per gram were saponified with sufiicient concentrated aqueous potassium hydroxide to saponify 95% of the saponifiable material. The process in general was carried out in precisely the manner as the procedure set forth in Example I. However, 8 extractions were made using ethylene dichloride with 5200 pounds (500 gallons) of ethylene dichloride used for the first extraction, 3120 pounds (300 gallons) for the second extraction and 2080 pounds (200 gallons) for each extraction thereafter. An amount of water was also added equivalent to the amount added in Example I. The following results were obtained:

Input weight 011 pounds 1250 Input vitamin Aunsap. basis Ls 21,376

Output yield (unsap.) pounds 59,233

At 780,000 A per gram or Ls 20,953

Output yield vitamin A per cent 98.02

EXAMPLE III To 500 parts by weight of soybean oil having a saponification value of 190and an unsaponifiable content of 0.55% were added 6.5 parts of 99% isopropanol by volume as a saponification catalyst'. While stirring, a solution of 110 parts of potassium hydroxide in 120 parts of water was added. This provided more KOH than required for complete saponification. The stirring was stopped after 12 minutes, at which time the soap mass was solid. The temperature at this stage was about 58 C. as against an original value of 25 C. The soap mass was allowed to stand at room temperature for four hours to insure complete saponification. Thereafter, 1260 parts of ethylene dichloride were stirred into the soap and, while mixing, the mass was heated to 60 C. When agitation was discontinued, a cleancut separation of the soap from the extracting solvent occurred. About A2% of the soap was in solution in the solvent at this temperature; hence it was unnecessary to add any water to that supplied by the alkali solution. The extraction was withdrawn and the soap extracted five more times with the same quantity of solvent and-in the same manner. The combined six extractions were cooled to 3 C. to precipitate the dissolved soap which was removed by filtration. The clear soap-free filtrate was then freed of solvent by distillation under reduced pressure. The yield of unsaponifiable matter was 2.75 parts or EXAMPLE IV 500 parts by weight of cottonseed oil having a saponification value of 188 and an unsaponifiable content of 0.53% were saponified with 108 parts of potassium hydroxide dissolved in 118 parts of water. The extraction procedure of Ex ample III was followed, and it was not necessary to add additional water, to obtain clean-cut separation of the soap from the hot (60 C.) solvent. Less than 1% of the soap was in solution in the combined extractions. The yield of unsaponifiable matter was 2.65 parts or 100%.

EXAM'PLE V 200 parts by weight of crude wool grease having a saponification value of 120 and an unsaponifiable content of 40% were liquified by heating to 45 C. The grease was then stirred during the adding of 8 parts of 99% isopropanol to catalyze the saponification and sufficient potassium hydroxide solution to saponify 115% of the oil based on the saponification value, that is, 28 parts of KOI-I in 31 parts of water. The mass was solid in 6 minutes and the temperature had risen to 52 C. To insure complete saponification, the soap mass was allowed to stand at room temperature for 18 hours. It was then mixed with 1000 parts of ethylene dichloride, and the mixture was heated to 60 C. while stirring. At this stage most of the soap was soluble in the hot solvent. Water was then added while stirring to obtain a separation of soap from the solvent. It required parts of water to precipitate all except about 1% of the soap from the solvent. The solvent layer was withdrawn and the soap heated to 60 C. with 500 parts of fresh solvent while stirring. When the agitation was stopped, immediate separation of soap from solvent occurred. The second extraction was withdrawn, and two more extractions were made in the same manner. These two latter extractions were nearly colorless, indicating that substantially complete extraction of the unsaponifiable matter had been accomplished by the first two extractions. The combined 4 extractions were cooled to 3 C. and then filtered. The clear filtrate was freed of solvent as in Example III. The yield of unsaponifiable matter was 78.9 parts or 98.8%.

The present application is a continuation-inpart of U. S. applications, Serial Nos. 486,214 and 533,256, the latter application now being U. S.

75 Patent No. 2,400,101.

attache as wane ass-he to secures-3i LettrsPa-trit s: a; slit of tfise at igna yiess than 1% eth ienesish "ride a, liiavingeseribeo my nvention that I' claifn dhsistingofydrocarbons and halogenatedrb'on's while maintaining the temperature or th solvent and soap-iromabout 40 C.- to just below the boiling point of the solveh ad the crite'ht of theso'apatsh'ch an amount th at t e' soapslightl'y soluble in thesol veiit ati-ng thwarm solveht extract froth the cap. I process ofrecovering the" iinsaponi'fi'able ract1on frorh a'naturally' occurring vitamin-free predominantly fatty materiai which com rises itying thevitamin-free: predominantly fat ti! material to p'ro'd iice seas massi extracting ify g thesoybean out the soap masswi-th ethylene dichloride" While tiemg e maintaining the ternpe'rature of the solvent and ethyie ediehionu' p a thewatr eo t f't t tha n ghtly-less the-ethylene titre o set-ween aho oprfoduceasoap with ethylene dichloride t "tul ef th ethyl;-

so" p betwe'e'n 4'0 andao" C. and the water con ee 0 1. 40% tn-t 0f thesoapat" 2,1'1' amount that the o fh' ':=s i soap is slightly soluble in the solvent and sepa-r'i amountth"t'slightIyless-thari 1 %-oi th seas grating the warm ethylene dichl'oride'extractfrom dissolves the" ethylndichldridg se a soap} t-heviiarih ethylene dichloride es act f 3. A process of recovering the unsapohifiable 1 fractioii f roma natfii al'ly occurring vitamin-free predominantly fatty material which comprises saponifying the vitamin-free predominantly fatty-material to produce a soap mass and successively, extracting the soap mass with portions of solvent ranging from about 1-1 to about 6-1 as compared to the weight of the original material, said solvent being selected from the" class consisting-of hydrocarbons ditjcarbons,While-maintaining t solvent an soap from about 40" the-boil point of the solve" content of" the soap at such soap isslightlysoluble-i-nth v p each oi -the warm soivent-extraets nom the warm dichloride ex separatethe'sosp tassel-red onsees Gil to o e soa with ihaintaini ng tempera-tn J elichloride aha soapat Btvfifi soap and combining the extracts. therein and removing the ethylene dichloride 4. A process of recovering the unsaponifiable from the extract. fraction from a naturally occurring vitamin-free 13, A process of recovering the unsaponifiable Predcminantly fatty material Which comprises fraction from wool grease which comprises sa- Sapo y g the Vitamin-free Predominantly ponifying the wool grease to produce a soap mass,

y material to produc a S p ss, eXtracting 5O extracting the soap mass with ethylene dichlothe soap mass with a solvent selected from the ride and soap at between about 40 to 80 C. and c s consisting or hydrocarbons and halogenat d the Water content of the soap at such an amount hyd a s, while a ain n e t mp u that slightly less than 1% of the soap dissolves of the Solv and p from about o ju in the ethylene dichloride, separating the warm below the b l po nt of the solvent and the ethylene dichloride extract from the warm soap, water content at Such an amo that the S p cooling the ethylene dichloride extract to sepais soluble to an extent of about A2 to in the rate the soap dissolved therein and removing solvent and separatin the warm solvent extract th ethylene dichloride from the extract,

from the warm soap. 14. A process of recovering the unsaponifiable 5. The process of ela m S d naturally fraction from soybean oil which comprises sacurring fatty m t al being of Vegetable Origihponifying the soybean oil with potassium hydrox- 6. T e Process o claim Said naturally ide to produce a soap mass and successively exur fatty material be o animal o tracting the soap mass with portions of ethylene 7. The Process f claim Sa d na y dichloride ranging from about 1-1 to about 6-1, curring fatty al being of vegetable orig as compared to the weight of the soybean oil,

e Process of claim Said naturally while maintaining the temperature of ethylene curring fatty material being of animal origindichloride and soap between 60 and C. and

A pr s of recovering th uns p n fi l the water content of the soap at such an amount fraction from a vitamin-free pre y fatty that the soap is slightly soluble in the ethylene dimateria1 of vegetable origin which comprises sa- 70 chloride and eparating t warm ethylene D y g the Vitamin-free Predominantly fatty chloride extracts from the warm soap. material with aqueous potassium hydroxide to 15. A process of recovering the unsaponifiable produce a soap mass, extracting the soap mass fraction from cottonseed oil which comprises sawith ethylene dichloride while maintaining the ponifying the cottonseed oil with potassium hytemperature of the ethylene dichloride and soap droxide to produce a soap mass and successively extracting the soap mass with portions of ethylene dichloride ranging from about 1-1 to about 6-1, as'compared to the weight of the cottonseed oil, while maintaining the temperature of ethylene dichloride and soap between 60 and 70 C. and the water content of the soap at such an amount that the soap is slightly soluble in the ethylene dichloride and separating the warm ethylene dichloride extracts from the warm soap. 16. A process of recovering the unsaponifiable fraction from wool grease which comprises saponifying the wool grease with potassium hydroxide to produce a soap mass and successively extracting the soap mass with portions of ethylene dichloride ranging from about 1-1 to about 6-1, as compared to the weight of the wool grease, while maintaining the temperature of ethylene dichloride and soap between about 60 and 70 C. and the water content of the soap at such an amount that the soap is slightly soluble in the ethylene dichloride and separating the warm ethylene dichloride extracts from the warm soap.

17. A process of recovering the unsaponifiable fraction from soybean oil which comprises saponifying the soybean oil with potassium hydroxide to produce a soap mass, successively extracting the soap mass with portions of ethylene dichloride ranging from about 1-1 to about 6-1, as compared to the weight of the soybean oil, while maintaining the temperature of the ethylene dichloride and soap between 60 and 70 C. and the water content of the soap at such an amount that the soap is slightly soluble in the ethylene dichloride, separating the warm ethylene dichloride extracts from the warm soap, combining the extracts, cooling the combined extracts to separate the amount of soap dissolved therein and removing the ethylene dichloride from the extracts.

18. A process of recovering the unsaponifiable fraction from cottonseed oil which comprises saponifying the cottonseed oil with potassium hydroxideto produce a soap mass, successively extracting the soap mass with portions of ethylene dichloride ranging from about 1-1 to about 6-1, as compared to the weight of the cottonseed 011, while maintaining the temperature of the ethylene dichloride and soap between and C. and the water content of the soap at such an amount that the soap is slightly soluble in the ethylene dichloride, separating the warm ethylene dichloride extracts from the warm soap, combining the extracts, cooling the combined extracts to separate the amount of soap dissolved therein and removing the ethylene dichloride from the extracts.

19. A process of recovering the unsaponifiable fraction from wool grease which comprises saponifying the wool grease with potassium hydroxide to produce a soap mass, successively extracting the soap mass with portions of ethylene dichloride ranging from about 1-1 to about 6-1, as compared to the weight of the wool grease, while maintaining the temperature of the ethylene dichloride and soap between 60 and 70 C. and the water content of the soap at such an amount that the soap is slightly soluble in the ethylene dichloride, separating the warm ethylene dichloride extracts from the warm soap, combining the extracts, cooling the combined extracts to separate the amount of soap dissolved therein and removing the ethylene dichloride from the extracts.

LORAN O. BUX'I'ON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

1. A PROCESS OF RECOVERING THE UNSAPONIFIABLE FRACTION FROM A NATURALLY-OCCURRING VITAMIN-FREE PREDOMINANTLY FATTY MATERIAL WHICH COMPRISES SAPONIFYING THE VITAMIN-FREE PREDOMINANTLY FATTY MATERIAL TO PRODUCE A SOAP MASS, EXTRACTING THE SOAP MASS WITH A SOLVENT SELECTED FROM THE CLASS CONSISTING OF HYDROCARBONS AND HALOGENATED HYDROCARBONS WHILE MAINTAINING THE TEMPERATURE OF THE SOLVENT AND SOAP FROM ABOUT 40*C. TO JUST BELOW THE BOILING POINT OF THE SOLVENT AND THE WATER CONTENT OF THE SOAP AT SUCH AN AMOUNT THAT THE SOAP IS SLIGHTLY SOLUBLE IN THE SOLVENT AND SEPARATING THE WARM SOLVENT EXTRACT FROM THE WARM SOAP. 